Realworld is a spinoff of Realpolitik with some additions and improvements. It adds support for up to 36 nationalities, "wings", and for coloring non-supply spaces by nationality. Realworld is required for the very large variants like World War IV

Cyberboard is a free-form board game program. It is used for many games besides Diplomacy. It allows free movement of pieces around the board, but does not do the adjudications for you like Realpolitik does. Cyberboard is useful for running any game where the map changes or pieces need to be moved around in non-standard ways, like Seismic or Deluge.